During this previous grant year, we have acquired 46 temporal bones, almost entirely those of children. Unfortunately, this year we did not receive any sets of temporal bones from the National Temporal Bone Bank Center. These temporal bones were processed, studied and were then included in our Temporal Bone Bank Library. At this time, our library now contains 250 complete temporal bones which have been studied. In addition, some 25 additional children have been studied and their audiograms included in our library of audiometric data against the time that they will die of their malignant disease and hopefully, the temporal bones will be acquired for our program for study. Dr. Yahomaso Okano who is experienced in Temporal Bone Histopathology, joined our laboratory as a full time research associate. His bibliography and curriculum vitae is enclosed. Dr. Okano is currently carrying out research on the fetal specimens which are included in the collection of the fetal specimens at the Cleft Palate Center at the University of Pittsburgh Dental School. 15,000 fetal specimens from 2 to 38 weeks of uterine life are available. About 30 fetal specimens were used in Dr. Okano's research to date. He is studying the fracture line which is found regularly between the round window niche and the posterior semi-circular canal ampulla. No one has previously reported examining this portion of the temporal bone in fetal specimens. Dr. Okano is examining slides at this point of 10, 12, and 15 week fetuses to study development of this region. In one side of the three fetal heads, the fissure between the round window niche and the posterior ampulla was observed filled with mesenchymal tissue. This is the same tissue found in the middle ear space and small blood vessels. This seems to contain a blood vessel. In fetal life, however, this appears as a fracture line. In later life, this and other work done with this fetal material available to us, should provide significant insights into the development of the ear and the temporal bone.